Flat panel display using Ti-Cr-Al-O thin film

Abstract

Thin films of Ti—Cr—Al—O are used as a resistor material. The films are rf sputter deposited from ceramic targets using a reactive working gas mixture of Ar and O 2 . Resistivity values from 10 4 to 10 10 Ohm-cm have been measured for Ti—Cr—Al—O film <1 μm thick. The film resistivity can be discretely selected through control of the target composition and the deposition parameters. The application of Ti—Cr—Al—O as a thin film resistor has been found to be thermodynamically stable, unlike other metal-oxide films. The Ti—Cr—Al—O film can be used as a vertical or lateral resistor, for example, as a layer beneath a field emission cathode in a flat panel display; or used to control surface emissivity, for example, as a coating on an insulating material such as vertical wall supports in flat panel displays.

What is claimed is:  
     
       1. A flat panel display, comprising: 
       a faceplate;  
       a backplate including electron emissive elements;  
       vertical support walls disposed within the flat panel display; and  
       vertical or lateral resistors comprising a Ti—Cr—Al—O thin film formed from powdered blends of 2-14% TiO 2  30-40% Al 2 O 3  and 50-65% Cr 2 O 3 , and disposed under the electron emissive elements to control surface emissivity of the backplate.  
     
     
       2. The flat panel display of  claim 1 , wherein said Ti—Cr—Al—O thin film has a thickness of about 0.2 μm to about 1.0 μm. 
     
     
       3. The flat panel display of  claim 1 , wherein said Ti—Cr—Al—O thin film is produced by a process including rf sputter deposition of a ceramic target. 
     
     
       4. A flat panel display of  claim 1 , wherein the vertical support walls are coated with the Ti—Cr—Al—O thin film. 
     
     
       5. A flat panel display of  claim 2 , wherein the lateral or vertical resistor is a thin film layer underlying the electron emissive elements. 
     
     
       6. A flat panel display of  claim 3 , wherein the Ti—Cr—O thin film has a resistivity range of 10 4  to 10 10  ohm-cm. 
     
     
       7. A flat panel display of  claim 6 , wherein the Ti—Cr—Al—O thin film comprises 1-3 at.% Ti, 15-20 at.% Cr, 10-20 at.% Al, and 58-70 at.% O. 
     
     
       8. The flat panel display of  claim 1 , wherein said Ti—Cr—Al—O thin film is produced by a process including rf sputter deposition of a ceramic target carried out using a reactive working gas mixture of Ar and O 2 . 
     
     
       9. The flat panel display of  claim 8 , wherein the process is carried out with a gas mixture composed of less than 2% O 2  with a balance of Ar.